Opal in Australia Click on a location on the map. 1. Lightning Ridge 2. Coober Pedy 3. Queensland This unique and unusual gemstone with its play of color and pattern is enthusiastically sought after around the world with Australia supplying over 95% of the world market. Lightning Ridge, Coober Pedy and several Queensland locations are the primary sources of opal within Australia. Cutting and Polishing of Opal Great care is always taken when cutting each stone. First, an opal cutter must decide on which way to cut the stone. This is done by using a diamond saw rotating at very high speed to cut the excess stone away so that the opal is revealed. Then the stone is placed on a wooden dobb stick to enable the cutter fine control over the stone when facing, shaping and polishing. The cutter uses a diamond dressed grinding wheel to rub down and expose the face of the opal. Once the process is complete the stone is shaped and all scratches removed ready for polishing. Polishing is undertaken on a felt-polishing pad using a fine polishing powder to give the stone its high gloss. The final process of cutting is to reshape the back of the stone so that it can fit comfortably in its setting such as a pendant or a ring.